1. Field of the Invention
This invention relates generally to bar code technology, and more particularly to a method and apparatus for capturing bar code information from a variety of video displays as well as other media, and using this bar code information in a variety of applications.
2. Problems in the Art
The use of bar code technology has proliferated as a means for efficient data collection. Generally, bar code technology allows for numbers, characters, or other symbols to be coded into a series of one-dimensional (1D) or two-dimensional (2D) spaced bars, as those terms are commonly known in the art. These bars are currently printed on the surface of particular objects. A good description of various bar code symbologies can be found in U.S. Pat. No. 6,149,059 to Ackley, herein incorporated by reference. Currently a bar code scanner is used to capture the pattern on the object, associated software decodes the bar code pattern, and the information from the decoded bar code pattern may be used as data and acted upon accordingly. One current method of reading bar codes is given in U.S. Pat. No. 6,039,252 to Maltsev, and is herein incorporated by reference.
However, there are currently no known easy means for capturing bar code patterns from a wide variety of video displays. Current methods for capturing bar code data from a composite video signal requires specialized and sophisticated camera and computer equipment. The use of such specialized and sophisticated camera and computer equipment is both cumbersome and expensive. It is therefore desirable to provide a means for capturing bar code patterns from a wide variety of video displays which is easy to use and relatively inexpensive.
Current bar code scanners have been incorporated into a wide variety of devices. Bar code scanners can now be found incorporated into other devices, such as a computer mouse or a personal digital assistant. However, none of these current devices are capable of reading bar codes from a video display. It is therefore desirable to provide a variety of devices with a bar code scanner capable of reading bar codes from a video display.
Currently, there are several problems associated with reading and decoding video displayed bar codes. First, a video displayed bar code to the human eye appears to be static. In reality, the video displayed bar code is flickering on and off many times per second. Second, a typical bar code reader has a low scan rate of 30 to 100 scans per second, which is not synchronized with the flickering video displayed bar code. Third, each type of video display has its own flicker, or refresh rate. Computer cathode ray tubes (CRT) commonly refresh from 72 Hz to 85 Hz. Computer liquid crystal displays (LCD) commonly refresh at 60 Hz. Around the world there are different standards for television CRTs which commonly refresh at 50 Hz to 60 Hz. It would be expensive to create a device to synchronize the flicker, or refresh, rates of multiple types of video displays with the scan rates of bar code readers.
Most current bar code scanners simply do not scan fast enough to ensure that a pixilated bar code image can be captured from a wide variety of video displays currently in use. It is therefore desirable to have a bar code scanner which is capable of capturing a pixilated bar code image from a wide variety of video displays.
The limiting nature of current bar code scanners also makes it difficult to interchange data across different computer operating systems and/or computer software applications. Currently, sophisticated computer software such as IBM DBT, Oracle, Microsoft SQL Server, or other programs, commonly referred to as middleware, are required in computer to computer data interchange applications. This middleware is expensive and requires a trained computer programmer to establish and maintain the data transfer links. Furthermore, middleware is not flexible. As business trading partners and suppliers change, and/or the format of data storage is modified in a host computer, the service of a trained computer programmer are required to maintain the data interchange capabilities. It is therefore desirable to minimize the amount of middleware software required.
Bar codes are currently one type of middleware. Current technology allows off screen media or printed bar codes to be used as “switches” to launch Internet web pages, complete complex machinery initialization and setup, dial a telephone number, etc. As the world moves toward a paperless society, it is desirable to provide a method for reading bar code switches which may be viewed on a video display.
There is therefore an unfilled need for a method and apparatus which solves these and other problems. This invention has as its primary objective fulfillment of this need.